Question

How to make sure that field is mandatory ? Here is what I mean

I have the following mysql table structure:

CREATE TABLE `new` (
  `id` int(11) DEFAULT NULL,
  `name` int(11) DEFAULT NULL,
  `phone` int(11) NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

Here is query with no data for phone

insert into new values(1, 'm', '');

But the query runs fine. What should be done so that mysql returns an error if there is no data for phone field? I can do that validation by php, but I’m curious how to do that in mysql.

Answer 1

INSERT INTO new VALUES(1,'m',NULL)

will cause error.
If you want to check whether is the phone number field is a blank string,
you can use a trigger in MySQL.